Saw this charger on Amazon and am curious if anyone has used it. Need a charger for a 2013 MBA and I was going to go with an OEM charger, but recall seeing some new ultra-portable chargers, namely Dart & Zolt. This particular one on Amazon is noticeably cheaper, but that makes me nervous it's not a good quality charger. If anyone has used one and can share their experience, I'd love to hear about it.